JPS61260066A - Method for synthesizing 2-imidazoline compound - Google Patents

Abstract

PURPOSE:To obtain the titled substance which is a precursor for imidazole compounds, etc., advantageously without forming sulfur compounds nor requiring a desulfurization step, by reacting a 1,2-aliphatic diamine with a nitrile in the presence of a silver compound as a catalyst under specific temperature conditions. CONSTITUTION:Preferably 1.0-1.1mol 1,2-aliphatic diamine expressed by formula I (R1 is H or methyl) is reacted with 1mol nitrile expressed by the formula R2-CN (R2 is aliphatic, alicyclic or aromatic group) in the presence of a silver compound as a catalyst at 150-250 deg.C under normal or higher pressure to afford the aimed compound expressed by formula II. A silver salt of an inorganic acid or organic acid, silver oxide, silver chloride, silver benzoate, etc., may be used as the silver compound which is the catalyst in an amount of 0.1-5pts. wt. based on 100pts.wt. 1,2-aliphatic diamine. Ethylenediamine, etc. may be cited as the 1,2-aliphatic diamine.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for synthesizing 2-imidazoline compounds by reacting a 1,2-aliphatic diamine with a nitrile in the presence of a silver compound as a catalyst.

(Industrial Application Field) The 2-imidazoline compound synthesized by the method of the present invention is a compound useful as a precursor of imidazole compounds and as a raw material for surfactants, bactericides, antistatic agents, and the like.

(Prior art) A 2-imidazoline compound can be produced by, for example, a method in which ethylenedi7mine salt is reacted with a nitrile at 100°C to 260°C (
Journal of the Chemical Society, 1947, pp. 497-505), but this method is unsatisfactory due to poor yield.

Also, a method of heating and condensing 1,2-aliphatic diamine and nitrile under an elemental sulfur catalyst is disclosed in Japanese Patent Publication No. 39-24965, and a method using elemental sulfur generated from phosphorus pentasulfide or sulfur chloride is disclosed in Japanese Patent Publication No. 40-8354. A method using hydrogen sulfide is described in Japanese Patent Publication No. 42-1548, and a method using carbon disulfide is described in West German Patent No. 842063.

(Problems to be Solved by the Invention) Each of the above methods has a low yield or produces a bad odor.
Furthermore, since they are accompanied by the production of sulfur compounds that act as poisons for dehydrogenation catalysts, they are unsuitable as methods for synthesizing imidacillin as an imidazole precursor in that they require a desulfurization step before the dehydrogenation step.

(Means for Solving the Problem) In order to compensate for this drawback, the present inventors investigated the catalytic action of many compounds other than sulfur compounds, and as a result, the present inventors found that a certain type of silver compound has the formula (II). It has been discovered that the imidacillin compound has a catalytic effect on the condensation reaction between the 1,2-aliphatic diamine and the nitrile represented by the formula (III), and the imidacillin compound represented by the formula (1) can be synthesized without the need for a desulfurization step. I found out.

Rz CN (III) ■ Rz (However, in the formula, represents a hydrogen atom or a methyl group, and R2 represents an aliphatic, alicyclic, or aromatic group.) (Effects of the Invention) The synthesis method according to the present invention Since no sulfur compounds are generated, there is little odor, and a desulfurization step as a pre-process for imidazole is unnecessary.

Therefore, the method of the present invention is simpler than known methods in terms of environmental measures and equipment, and since the catalyst used can be easily recovered, imidacillin can be synthesized economically.

Typical starting materials 1.2-aliphatic diamines used in the process of the present invention are ethylenediamine, 1,2
-propylene diamine, and the nitriles include acetonitrile, propionitrile, benzonitrile, lauronitrile, steanitrile, etc.

As the silver compound of the catalyst, an inorganic acid, a silver salt of an organic acid, silver oxide, silver chloride, silver acetate, silver benzoate, or a double salt of an imidazole compound (eg, silver nitrate double salt, silver sulfate double salt) is used.

The amount of catalyst used is 0.1 to 5 parts by weight per 100 parts by weight of the 1,2-aliphatic diamine.

1.2-The reaction between the aliphatic diamine and the nitrile is carried out in the presence of each of the above silver salts or double salts at a temperature of 100°C to 300°C, preferably 150°C to 250°C, under normal pressure or increased pressure. This reaction does not require any particular solvent.

The starting materials may be equimolar to each other or one may be in excess. Preferably, the reaction under pressure using 160 to 1.1 mol of 1,2-aliphatic diamine per 1 mol of nitrile produces 1,2-aliphatic diamine, The mixture of nitrile and the catalyst is heated in a pressurized vessel at the reaction temperature for 1 hour, and then once cooled to release the generated ammonia, the reaction mixture in the vessel is further heated at the reaction temperature for 1 hour. be exposed.

In the atmospheric pressure reaction, a mixture of nitrile and catalyst is first reacted with 15
The mixture is heated to 0° C., 1,2-aliphatic diamine is added dropwise thereto, and the reaction temperature is maintained for 8 to 12 hours. The ammonia generated is then discharged via the bubble needle.

The target product is purified by conventional vacuum distillation.

Next, the method of the present invention will be specifically explained with reference to Examples.

Example 1 30 g (0.5 mol) of ethylenediamine and 20 g of acetonitrile in a 300'cc stainless steel autoclave.
．． 5 g (0.5 mol) and 0.6 g of silver nitrate were heated to 200° C. for 1 hour while stirring. (The pressure in the autoclave was 22 kg/ad.) Then, after cooling (pressure was 5 kg/aa), the generated ammonia was released, and the reaction system was heated again at 200° C. for 1 hour. (The pressure is 20kg
It became /-. ) After cooling (pressure was 4 kg/ctA), the ammonia was released.

As a result of gas chromatography analysis under the following conditions, the reaction solution thus obtained contained 65 mol % of 2-methylimidacyline.

[Gas chromatography conditions]

Column inner diameter x length; 3m x 1m column temperature
・125℃→200℃ carrier gas type and flow rate; Hl, 50cc/si
n Detector - FID Example 2 In a 300 cc stainless steel autoclave, 30 g (0.5 mol) of ethylenediamine and 20.
5 g (0.5 mol) and 0.6 g of silver acetate were heated to 200° C. for 1 hour while stirring. (The pressure in the autoclave was 20 kg/cd.) Then, after cooling (
The pressure was 4 kg/aJ) The generated ammonia was released, and the reaction system was heated again at 200° C. for 1 hour. (The pressure is 18kg
It became /-. ) After cooling (pressure was 3 kg/cJ), the ammonia pressure was released.

As a result of gas chromatography analysis under the same conditions as in Example 1, the reaction solution thus obtained contained 45 mol% of 2-methylimidacyline.

Example 3. In a 300 CC stainless steel autoclave, 18 g (0.33 mol) of propylene diamine, 25 g (0.33 mol) of zolobionitrile, and 0.5 g of silver nitrate were stirred and heated to 200° C. for 1 hour. (The pressure in the autoclave was 18 kg/aa.) Then, after cooling (the pressure was 4 kg/aa), the generated ammonia was released, and the reaction system was heated again at 200° C. for 1 hour. (Pressure is 1
It became 7 kg/-. ) After cooling (pressure was 3 kg/aa>ammonia was released).

As a result of gas chromatography, the reaction solution thus obtained was found to have a concentration of 70
Contains mol% of 2-ethyl-4-methylimidacyline.

Example 4 3 communicated with outside air via soda lime drying pipe and bubble meter
In a 00 cc flask, 103 g (1 mol) of benzonitrile was stirred and heated to 150° C. with 1.5 g of silver nitrate. Next, 63 g of ethylenediamine (
1.05 mol) was added dropwise so that the temperature inside the system did not fall below 150°C, and after the addition was completed, the reaction system was heated to 180°C, and at this temperature for 8 hours until the generation of ammonia could no longer be confirmed with a bubble meter. Heated.

As a result of gas chromatography, the reaction solution thus obtained was 78
Contains mol% of 2-phenylimidacilline.

Example 5 3 communicated with outside air via soda lime drying tube and bubble meter
103 g (1 mol) of benzonitrile and 1.4 g of silver nitrate were stirred and heated to 150° C. in a 00 cc flask. Next, 63 g of ethylenediamine (
1.05 mol) was added dropwise so that the temperature in the system did not fall below 150°C, and after the dropwise addition was completed, the reaction system was heated at 180°C for 12 hours.

As a result of gas chromatography, the reaction solution thus obtained was found to have a concentration of 40
Contains mol% of 2-phenylimidacilline.

Example 6 3 communicated with outside air via soda lime drying tube and bubble meter
In a 00 cc flask, 103 g (1 mol) of benzonitrile was stirred and heated to 150° C. with 1.5 g of silver nitrate. Next, 77g of propylene diamine was added to this system.
(1.04 mol) was added dropwise so that the temperature inside the system did not fall below 150°C, and after the addition was completed, the reaction system was heated to 180°C. At this temperature, the reaction system was heated until the generation of ammonia could no longer be confirmed with a bubble meter. heated for an hour.

As a result of gas chromatography, the reaction solution thus obtained was 75
Contains mol% of 2-phenyl-4-methylimidacyline.

Example 7 3 communicated with outside air via soda lime drying tube and bubble meter
In a 00 cc flask, 103 g (1 mol) of benzonitrile was stirred and heated to 150° C. with 1.5 g of silver nitrate. Next, 77g of propylene diamine was added to this system.
(1.04 mol) was added dropwise so that the temperature in the system did not fall below 150°C, and after the dropwise addition was completed, the reaction system was heated at 180°C for 12 hours.

As a result of gas chromatography, the reaction solution thus obtained was found to be 45
Contains mol% of 2-phenyl-4-methylimidacyline.

Example 8 3 communicated with outside air via soda lime drying tube and bubble meter
181 g of lauronitrile (1
mol) with 1.0 g of silver nitrate at 150°C.
It was heated until. Next, 63g of ethylenediamine was added to this system.
(1.05 mol) was added dropwise so that the temperature inside the system did not fall below 150°C, and after the dropwise addition was completed, the reaction system was heated at 200°C for 12 hours.

As a result of gas chromatography, the reaction solution thus obtained was found to have 65
Contains mol% of 2-dodecylimidacilline.

Example 9 3 communicated with outside air via soda lime drying tube and bubble meter
While stirring 181 g (1 mol) of lauronitrile with 1.4 g of silver benzoate in a 00 cc flask,
Heated to ℃. Then, in this system, ethylenediamine 63
g (1.05 mol) was added dropwise so that the temperature in the system did not fall below 150°C, and after the addition was completed, the reaction system was heated at 200°C for 12 hours.

As a result of gas chromatography, the reaction solution thus obtained was found to have a
Contains mol% of 2-dodecylimidacilline.

Example 10 3 communicated with outside air via soda lime drying tube and bubble meter
132°5g of stearonitrile in a 00cc flask (
0.5 mol) with 1.0 g of silver acetate while stirring
It was heated to 50°C. Next, 31 g (0.52 mol) of ethylenediamine was added dropwise into the system so that the temperature inside the system did not fall below 150°C, and after the addition was completed, the reaction system was heated to 200°C for 12 hours.
heated for an hour.

As a result of gas chromatography, the reaction solution thus obtained was found to have a concentration of 60
Contains mol% of 2-heptadecyl imidacillin.

Example 11 3 communicated with outside air via soda lime drying tube and bubble meter
132°5g of stearonitrile in a 00cc flask (
0.5 mol) of 2-methylimidazole silver nitrate double salt 2g
The mixture was heated to 150°C while stirring.

Next, 31 g (0.52 mol) of ethylenediamine was added dropwise into the system so that the temperature within the system did not fall below 150°C.
After the dropwise addition was completed, the reaction system was heated at 200° C. for 12 hours.

As a result of gas chromatography analysis under the same conditions as in Example 10, the reaction solution thus obtained contained 25 mol % of 2-heptadecyl imidacillin.

Claims (1)

[Claims] 1,2-aliphatic diamine represented by formula (II) and formula (III)
) in the presence of a silver compound catalyst 15
Formula (I) characterized by heating at 0°C to 250°C
) A method for synthesizing a 2-imidazoline compound shown in ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) R_2-CN(III) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (However, R_1 in the formula represents a hydrogen atom or a methyl group, and R
_2 represents an aliphatic, alicyclic, or aromatic group. )